Method of making axles



June 10, 1930. E. c. MoGFoRD ET AL METHOD OF MAKING AXLES Original Filed May 15, 1929 5 Sheets-Sheet 1 E. c. MOGFORD ET AL.

METHOD oF MAKING AxLEs `lune 10, 1930. 1,762,407

Original Filed May 15, 1929 5 Sheets-Sheet 2 f v l 7266.56 nuenfov w fg Zune/77209 w. i

` e Ory e 27 June 10, 1930. E. c. MOGFORD Er AL 1,762,407

METHOD QF MAKING'AxLEs Original Filed May l5, 1929 3 Sheecs-SheecI 3 57m Patented June 10, 1930 UNITED STATES PATENT OFFICE EDMUND C. MOGFORD AND GEORGE SPATTA, OF BUCHANAN, MICHIGAN, ASSIGNOBS T0 CLARK EQUIPMENT COMPANY, OF BUCHANAN, MICHIGAN, A CORPORATION 0F MICHIGAN METHOD or lMAKING Ax'LEs original applic-ation med Mayas, 1929, serial No. 369,962. Divided and this application med November 22, 1929. serial No. 409,094.

,pending' application Serial No. 363,362 filed May l5, 1929, and' discloses a tubular axle of the reverse Elliot type. 'However the method of constructing axles disclosed in this invention is not limited to the construction of axles of this particular type. f

Forged axles are known and have been ac,- cepted in automotive construction. Tubular axles of the Elliot type are also known.

In such known tubular axles the end yoke and spring pad-are forged from solid metal' and the scrapping of considerable metal is entailed in the process of machining. This is avoided in our method of construction as the spring pads are of pressed steel and the metal in the end ofthe tubing can be forged very nearly to the size required with much less work or machining and less waste of metal.

Our method of constructing axles may'also beemployed -in axles of the Elliot type and constitutes an improvement over devlces of l the prior art.

vIn such tubular axles of the prior art the tubing is ofthe same section from end to end whereas in the axle made inl accordance with the teachings of our invention the arms are upset from a region under the springpads to the outcrendsthus strengthening and stiffening the axle where fthe. maximum bending moment occurs. As compared with an axle ofthe same strength, an axle made in accordance with the teachings of our invention is -much lighter thanv an axle of either the solid forged type or the prior known tubular axles, for example,

the particular embodiment hereinshown 1s at least twelve pounds lighter than the corresponding* size of forged axle.- This saving in unsprung weight 1s,-of course, a great advantage/as .iswell .known to thoselskilled inthe art. In carrying out our .ends of a tubular blank by endwise forging to give the desired strength-to the arm under the outwardly towards the wheels. Forged knuckle pieces are inserted in the end of the tube and secured therein by one of a number of Ways, as, for example, by weldingforging pinning, ora combination of these actions.y

The axle is then formed `to shape and theJ spring pads are welded in place. The spring pads are. preferably madeof `sheetmetal stampings, although for certain purposes forglngs may be used.

e The forming is preferably done-in a press,

which,'upon forming the axle, quenches itv and holds it to form. This provides. both heat treatment and prevents warping.

Now. in order to acquaint those skilledin the art with the manner of constructin an axle in accordance withthe teachings o our invention, we shall describe.' in conjunction with the accompanying drawings 'a specific embodiment of the invention.

v the same;

Flgure 4 lis a 'transverse'v section through one of the arms taken on the line '4'-4 of Figure 3;. l

Figure 5 is a fragmentary view shbwing. the manner of attaching the springs to the spring seat;

:Figure Gis a fragmentary side view of 'a modifiedl form-of spring seat and shock absorber hanger;` y

Figure Gais a plan view' of the same;

Figure 7 is' a fragmentary longitudinal section 'through a'modiied 'form of axle employing the forged knuckle seat;

Figure 8 is` a longitudinal verticali'section .I

through theblank which is employed in manufacturing the axle; Figure Q is a similar section through the 'blank after the first'i step4 of `reducing the invention, we upset the f diameter of the ends;

after the first upsetting operation;

Figure '11 is asimilar view of the end of the tubeshowing a second upsetting opera- 'tion to adapt the tube to be attached to the knuckle piece by Ka forging or pressing operation;

Figure l2 isa longitudinal section .through the tube and the knuckle piece showing'the v metal of the tubepressed or for ed into the 'recesses inthe shank of the knuc le piece;

Figure`13 is asection taken on .the line 13--13 ofFigure 11 showing'the excrescences of metal produced by the second upset' operation; i

Figurev 14 is a section taken on the .line 14-14 of Figure 12 showing the projection of the tube walls inwardly to grip the shanks of the ,knuckle piece; y

c Figure 15 is a longitudinal vertical section through the end of the tube showing a modidies employed inthe press of Figure 16; and

. Figures andit .comprises a` tubular member Figures 18 and 19 are la side view and a bottom'plan view, respectively, ofthe pressed metal spring clip. l

Referring now to Figures'2, 3,` 4 and 5, the completed4 tubular axle .isv shown in these 1 having the arms 2 and 3 with knuckle pieces 4v and 'secured'to the endsof the arm.- 1 The knuckle pieces 4 and 5 are drilled vas indicated at 6 'and -7 for thereceptionof knuckle pins for the front wheels.

` Thebores 6 and 7 are set at an angle. so

thattheaxis ofthe knuckle pin intersects the ksupporting surface at a point somewhat .in advance of or at :the bearing ofthe tire upon the road` as is well known to those skilled in the art. The tubular -member or body 1 is constructed of a piece ofseamless steel tubing, the blank therefor being shown in Figure 8. The tube is initially of approximately two and one .fourth inches in diameter three sixteenth inches.

and has a wallthickness of approximately The outer ends or arms 2 and 3 are "thickened by endwise upsetting at points lying Within the spring seats 8 and -9 as may be seen 1n.y Figure 3. The outer-vends of the arms 2 and 3 are reduced in` diameter externally andare formed into the 'shape of tubular conical sockets as indicated at 12fand 13, the walls lbeing brought to a maximum.thickness at the inner ends vof the sockets as indicated at 14 and 15. The ysockets 12 and 13 receive the Shanks 16 and sockets)4 and 'are then secured by circumferential wells as at18 and 19 to the knuckle pieces, shoulders being provided on thev knuckle pieces adjacent the ends ofthe tube roove which is filled The shanks 16 and 17 are pinned to the ends of the tubes preferably Aby welded pins or' 'plugs-as shown in Figure 4 although tapered or riveted pins may be employed Aif desired. The welding isl accomplished by' drilling a recess at each side through the socket and into the body of the. shank and then producing by welding, as by means of an electric arc, the plugs20 and 21 which at the same time are fused to bolt the body ofthe shank and the walls of the socket. Thereby, the circumf erential o r vhoop strength of the socket is not impaired and it is not necessary to drill away the body of the shank `to anl extent which would materially weaken the same The pins 20 and 21 are placed principally on the horizontal neutral axis of the axle so that the beam strength of the axle is not materialvly impaired The welded pins 20 and 21 are j highlyadvantageous in taking the torque reaction of the wheel vupon the arm of the axle.

. The inner welding line of the plug through the shank lies below the dividing line between Jshank and socket so thatthe weld is not in shear but the body of the plug such as 2O or A The spring pads 8 and 9 which are shown more in detail in Figures 18 and'19 arepreferably 'made of pressed sheet metal or platestock and comprise' a flat platform portion 23 upon which] the lower4 leaf of the leaf spring 24 rests. l

A'pair of wings 25 integral with .the platformportion 23 are formed into a cylindrical shape to lit the outer cylindrical surface of the axle, the ends of the platform portion .23 extending outwardly, preferably'beyond the diameter of the tube so as to form corners 26 in .which U-bolts 27 .and 28 are adapted to lie. The U-bolts are connected together by yokes 29 and 30, the"yokes being just long enough to permit the leaf spring to lie between the sides of the shanks of the bolts and the seats or saddles 25- 25, extending around the circumference of the tube less than halfway so that the said seats or saddles 25 are embraced betweenthe shafts of the U-bolts 27 and 28. .This provides alight and compact spring seat. These Vcurved wings which form the saddles or seats 25--25 arethen welded valong their edges to the tubular member landwith such welding the seats form rigid support against which the U-bolts may draw to secure a very firm grip upon the axle. The platform portion 23 is provided with'a hole 32 stud in the center of the spring.

In attaching the spring seat, the axle and `clips or seats 8 and 9 are held in a jig while the edges 33 are fastened by hand welding and then the circumferential welds along the edges 35 of the saddles or seats 25 are machinewelded. Obviously, this could be done by hand. The extended welds along the edges' provide a secure attachment between the spring seat and axle.

In Figure 6, I have shown a modified form of spring seat in which the spring seat is formed of a forging. In this case, since the bottom is a solid cylindrical surface, extend` ed wings or seats are not required and the weld 37 at each side does not interfere with the location of the bolt as shown in Figure 6, so that the cylindrical seat can be more extensive and can extend over a wider arc on the surface of the tube. A weld 37 forms a fillet in the cornerbet-ween the side Wall'of the seat member 38 so that it need not interfere with the shank of the U-bolts such as 27 and 28.

As shown in Figures 6 and 6, such forged spring seat may be provided with an arm 40 forming a shackle 39 for attaching the strap of a shock absorber or rebound check, such shackle having an eye 41 or being otherwise formed to receive the end of a strap or of a cable which may be employed for this purpose. If a two-'Way shock absorber is to be g employed, it is to be understood that these .dimensions are optional.

The end of the tube is first swaged down as by rolling to taper the outer end as indicated at 45 in Figure 9. This results in a slight elongation of the blank and a slight thickening of the Walls of the outer end which lateiforms the arms 2 and This rolling down is preferably accomplished at each end either.simultaneously or individually and is preferably done hot. The tube is then brought to a proper forging heat and is u set endwise to thicken the walls about t e entire periphery of the part which is upset, at a point within the place where the spring seat, such as 8 or 9, is later attached.

At the same time, or by subsequent operation, the upsetting of the outer end to form the socket 12 is accomplished, the inside diameter of the socket being held to a definite shape. by a mandrel and maximum Wall thickness ofthe tubular blank being produced justv back of the socket as indicated at 14 in Figure 10.

` A The sockets 12 and 13 are then reamed out to an accurate diameter and tlie'shanks such as 16 and 17 of .the knuckle pieces 4 and 5 are accurately machined and pressed in with a press fit into the sockets 12 and 13, these parts being carefully held in alignment and the shaft or body of the tube being straight as indicated in Figure 1. y Then the circumferential welds 18-18 are formed, this operation preferably being performed by machine although it may be done by hand.

Then the pockets for receiving the welds 2() and 21 are drilled and the said weld's are made between the shank and walls of the socket. yThe drilling of the pockets may occur before the circumferential Welds 18 and 19 are made so that the two welding operations may be accomplished at substantially the same time.

This leaves the axle in the shape shown in Figure 1 and it is now ready for forming. The axle is then heated preferably throughout its entire length or it ma be heated only at the point where it is to ie bent, that is, just outside of the place where the spring seat will later be fastened. Then it is placed in the press shown in Figure 16 and laid in the die 47 which has a groove to receive the 'i axle as shown in Figure 1.` The lower die 47 has a spring follower plate 48 which is adapted to be held in position by suitable follower springs indicated at 4S). This spring follower plate 48 is provided with a seat for receiving the shaft or body of the axle and to `hold the same with sufficient rigidity that the upper die member 50 in engaging the body of the axle secures a firm grip upon the same. Then the upper die member 50 forces the axle down to bend the axle into the shape shown in Figure 2.

The lower die member 47 is preferably mounted upon a plunger member 51 which plunger member may be connected to a hydraulic piston in a cylinder 52 and subjected to a predetermined hydraulic pressure in a connected accumulator 53, subject to airpressure of a predetermined value.

This holds the lower die member 47 in elevated position with a predetermined force which is sufficient in cooperation with the upper die member 50 to form the body of the axle to the desired` shape. v

A box member 54 surrounds the plunger and this box or chamber contains a bath of quenching liquid 55 which may be water or oil, or the like, the level of which is belowT y the top of the lower die member 47 when the latter is in elevated position.

The upper die member 50 is preferably' mounted on a hydraulic plunger 56 having an operating cylinder 57 capable of exerting a -pressure in excess of the predetermined pressure, sustaining the lower die member.

The operation is as follows:

The lower die member 47 being elevated as shown inFigure 16 and the axle member being placed in the lower diemember, hydraulic pressure is admitted to the upper end of the piston connected to the plunger 56 causing the plunger to travel downwardly to carry the upper die member 50 into engagement with the body of the axle, depressing the follower plate 48 and forcing the axle, to conform to the shape of the die. Further pres- .sure overcomes the resistance of the plunger 51 and both dies are then brought down into the bath 55 with the axle held between them in such position that it is incapable of warp ing during` cooling andthe axle is thereby quenched and atthe same vtime held tothe desired shape.

The pressure is then released upon the upf per side of the piston of the plunger 56 and the pressure on the lower side of the plunger 51 causes the same to be raised to its upper limit, and then the pressure applied to the lower side of the piston connected to the plunger 56 causes the die member 5() to be raised to clear the lower die and the'contained axle. The axle is then removed.y and thereafter the spring seats 8 and 9 are attac-hed by Welding as previously7 described to provide the completed axle shown in Figure 2.

In Figure 7 I have shown a modified form of the axle of the Elliot type where the forked knuckle piece 58 is provided. The arm 2 is thereby'shortened but the formation of the shown the manner of attaching the knuckle piece and the end of the arm by pressing or forging operation to interlock the shank 60 of the knuckle piece 61. vIn this case, after the operation of forming the tapered socket 12 of Figure-10, the end of the arm is upset in a die to produce the protuberances 634-63 u pon the outside walls of the socket.- The ing f side walls are tapered as in Figure 10, the' sockets being, however, shortened by ,such operations, to-provide the increased metal for theV protu'berances 63. l Y l The shank 60 is provided with parallel-cor? rugations or grooves across-the topandl bottom of theshank as indicated4 at 64, the shank 'pheral Weld about the margins of the .Sbket otherwise being machined and being pressed into the socket. Thenext operation is a pressing or forging of these protuberances 63 into therecesses 6 4 ori the inside wall of the socket. That is to say, .the outside wall of the vsocket isbrought to a circular form tapered'outside.

The excess metal which Was-contained in the p rotuberances 63 which formed ridges of lunar shape upon the top and bottom of the 'i sockets is thereby forged into the pockets or corrugations 64 as .indicated at 65 in Figure 12. This disposal of the metal on top and 4bottom places it in a position where it has maximum value for increasing the moment of inertla 1n bending. The operation of forcing the metal inwardly may be performed in a suitable two-part die engaging top and bottom of the outside of the socket.-

Instead of grooves such as 64 across the -on theoutside Vof the-socket which is then forced into such recesses 68-68 to providev the interlocking projections 69-69 connecting thesocket, and the shank 66 firmly together. The outer margins of vthe sockets andthe shanks may be welded if desired but if' properly forged this is-not necessary.

` An advantage of the welded form is that the inside of the body is completely closed off 'from the outside so that moisture cannot get into the inside and corrode the axle.

Tests made upon this axle indicate its superiority inlperformance as againstV axles of' the prior alt. The tubular shape of the body of the axie is highly desirable becauseof the ymaximum strength against bending in any direction and also because of its ,high torsional strength. y

The bent ends or arms 2 3, which are connected to the wheels form crank arms which particularly under the action of heavy break- `ing of the vehicles tend to twist the axle with respect to the spring. The Welding of the seats 8 and 9 to the body of the axle provides a hold which is highly resi'stant to such torsional stresses aswell as to other stresses which are incidental to the use of the axle.

Wedo not intend to be limited to the details shown and described.

What wel claim ist. Y

which comprises tapering the end -portions of 'the tubular blank, upsettig said end portions to increase the wall thickness and to form a. tapered socket in the'outr end, forging a knuckle piece with a. tapered shank, driving.

said shank into the socket, and forming apeand shank.

2. In the method of forming a tubular axle out of a blank of seamless tubing which comprises tapering an end portion of the blank,

V1. The method of frmingatubular axle l upsetting said end portion lo increase the i welll thickness thereofand to form a tapered ysocket, forging a knuckle piece with a ta pered shank, driving said -shank into the y socket and welding/the socket and. shank totothe walls of said recess'to unite the shank and socket.

, 4. The method of forming a tubular axle which comprises tapering` the end portions of a tubular blank, upsetting said end portions to increase the wall thickness thereof and to form -a socket in the outer end, forming a knuckle piece with a shank, introducing said shank into the socket,l forming a peripheral' weld about the margins of the socket and the shank,.forming a recess through the walls of'jthe socket and into the shank and welding metal to the Walls of said recess to fill the same.

5. In the method of forming a tubular axle f the following steps, viz., tapering the end portions of the tubular blank, upsetting said end portions to increase the wall thickness thereof and to form tapered sockets, forging knuckle pieces with tapered shanks, driving said shanks into the socket, forming peri h.- eral Welds about the margins of they soc et and the shank, forming recesses througih the walls of the socket and into the shan and welding metal to the walls of said recesses to fill the same. v

6. The method of forming a tubular axle which comprises tapering the end portion of a tubular blank, upsetting said end portion to increase the wall thickness therof and to form a socket, forming a knuckle piece with a shank, forcing said shank into said socket, forming a recess through the wall of the socket and into the shank and welding metal to the walls of said recess to fill the shank.

7. The method of forming a tubular axle out of a blank of thin walled tubing which comprises upsetting the walls-of the blank to thicken them at the points of maximum stress,

tapering the end portions of the blank, upset.

ting sald end portions to `increase the wall thickness therof and to form a tapered socket, forging a knuckle piece with a tapered shank, driving said shank into the socket, and welding the socket and shank together.

9. The method of forming a tubular front axle from a thin walled seamless tube which comprises heating, and endwise upsetting the tube Vto thicken its walls about the 4entire periphery of the tube and form a spring lsupport, heating, tapering, and upsetting the end sections of the blank, and forming the end sections to sha e. v 10. The metliod of forming a tubular front axle from a thin walled tubular blank whichV comprises, heating and endwise upsetting the blankito thicken, its walls substantially uni- Y a tubular axle crease only the erimeter of the inside-of the tube,.tapering t 1e end portions of the blank, upsetting said end portions to increase the wall thickness thereof `andto form a tapered socket, forging a knuckle piece with a tapered shank, driving said shank into the socket,

'and welding the shank 'and socket together.

12. The methodv of forming a tubular front axle from a thin walled tubular blank which comprises, heating a section of the blank, supporting the blank at that heated section, upsettingthe blank to thicken the walls-at that ysection by decreasing the perimeter of only the inside surface, heatin the end section of the blank, and upsetting he end section and forming said end section to shape.

13. In a method of making a tubular axle, the combination of the following steps, heating a thin walled tubular blank, upsetting the Wall by endwisepressure to produce a thickened wall back of one end thereof at a point where a spring seat is to be located forming a spring seat with a concave bottomlwall fitt1n the wall of the blank where itis upset,

an welding the edges of the seat to the thick- 8. The method of forming a tubular axle i out of a blank of seamlesstubing which comprises heating the blank at the points at which-the spring supports are'to be located, endwisel upsetting the walls of the blank at those points to'thickenithem about the'entire periphery of the blank, heating the end portions of the blank, and tapering and upset-y tin said end portions to form them to the desired shape and wall 

